How to become a sponsor

Please contact us for sponsor arrangements. Both recurring and one-time contributions are most welcome. Contributions towards a specific issue or feature are also possible, and can be attributed to your company in our release notes and other related materials. Hardware-only contributions, whether new or used, are also extremely helpful and well received, especially if you find a device that doesn't work. Please see our donation transparency report for past hardware contributions.

Features

OS support

Android

Supports versions 2.3.3 (SDK level 10) to 8.1 (SDK level 27)

Supports Wear 5.1 (but not 5.0 due to missing permissions)

Supports Fire OS, CyanogenMod, and other heavily Android based distributions

root is not required for any current functionality

Remote control any device from your browser

Real-time screen view

Refresh speed can reach 30-40 FPS depending on specs and Android version. See minicap for more information.

Rotation support

Supports typing text from your own keyboard

Supports meta keys

Copy and paste support (although it can be a bit finicky on older devices, you may need to long-press and select paste manually)

May sometimes not work well with non-Latin languages unfortunately.

Multitouch support on touch screens via minitouch, two finger pinch/rotate/zoom gesture support on regular screens by pressing Alt while dragging

Status

STF is in continued, active development, but development is still largely funded by individual team members and their unpaid free time, leading to slow progress. While normal for many open source projects, STF is quite heavy on the hardware side, and is therefore somewhat of a money sink. See how to become a sponsor if you or your company would like to support future development.

We're also actively working to expand the team, don't be afraid to ask if you're interested.

Short term goals

Here are some things we are planning to address ASAP.

Performance

Properly expose the new VNC functionality in the UI

Properly reset user data between uses (Android 4.0+)

Automated scheduled restarts for devices

More!

Consulting services

We highly encourage open participation in the community. However, if you're running a business that uses STF or would like to use STF, you may sometimes want to have an expert, i.e. one of the original developers or a skilled contributor, work with you to set up a prototype for evaluation purposes, add support for new or old hardware, figure out an issue, fix a bug or add some new feature. Our services are similar to FFmpeg's. Contact us with details and we'll see what we can do.

Availability is limited and tied to individual developer's schedules.

A quick note about security

As the product has evolved from an internal tool running in our internal network, we have made certain assumptions about the trustworthiness of our users. As such, there is little to no security or encryption between the different processes. Furthermore, devices do not get completely reset between uses, potentially leaving accounts logged in or exposing other sensitive data. This is not an issue for us, as all of our devices are test devices and are only used with test accounts, but it may be an issue for you if you plan on deploying STF to a multiuser environment. We welcome contributions in this area.

On Windows you're on your own. In theory you might be able to get STF installed via Cygwin or similar, but we've never tried. In principle we will not provide any Windows installation support, but please do send a documentation pull request if you figure out what to do.

Note that while Mac OS can be used for development, it doesn't provide a very reliable experience in production due to (presumed) bugs in ADB's Mac OS implementation. We use CoreOS but any Linux or BSD distribution should do fine.

Installation

As mentioned earlier, you must have all of the requirements installed first. Then you can simply install via NPM:

npm install -g stf

Now you're ready to run. For development, though, you should build instead.

Building

After you've got all the requirements installed, it's time to fetch the rest of the dependencies.

First, fetch all NPM and Bower modules:

npm install

You may also wish to link the module so that you'll be able to access the stf command directly from the command line:

npm link

You should now have a working installation for local development.

Running

STF comprises of several independent processes that must normally be launched separately. In our own setup each one these processes is its own systemd unit. See DEPLOYMENT.md and Setup Examples if you're interested.

For development purposes, however, there's a helper command to quickly launch all required processes along with a mock login implementation. Note that you must have RethinkDB running first.

If you don't have RethinkDB set up yet, to start it up, go to the folder where you'd like RethinkDB to create a rethinkdb_data folder in (perhaps the folder where this repo is) and run the following command:

rethinkdb

Note: if it takes a long time for RethinkDB to start up, you may be running into rethinkdb/rethinkdb#4600 (or rethinkdb/rethinkdb#6047). This usually happens on macOS Sierra. To fix this on macOS, first run scutil --get HostName to check if the HostName variable is unset. RethinkDB needs it to generate a server name for your instance. If you find that it's empty, running sudo scutil --set HostName $(hostname) has been confirmed to fix the issue on at least one occasion. See the issues for more complete solutions.

You should now have RethinkDB running locally. Running the command again in the same folder will reuse the data from the previous session.

You're now ready to start up STF itself:

stf local

After the webpack build process has finished (which can take a small while) you should have your private STF running on http://localhost:7100. If you had devices connected before running the command, those devices should now be available for use. If not, you should see what went wrong from your console. Feel free to plug in or unplug any devices at any time.

Note that if you see your device ready to use but without a name or a proper image, we're probably missing the data for that model in our device database. Everything should work fine either way.

If you want to access STF from other machines, you can add the --public-ip option for quick testing.

stf local --public-ip <your_internal_network_ip_here>

Updating

To update your development version, simply pull the repo and run npm install again. You may occasionally have to remove the whole node_modules and res/bower_components folder to prevent NPM or Bower from complaining about version mismatches.

FAQ

Can I deploy STF to actual servers?

Will I have to change battery packs all the time?

No, not all the time. Aside from a single early failure we had within only a few months, all of our devices were doing fine for about two years. However, having reached the 2-3 year mark, several devices have started to experience visibly expanded batteries. Expanded batteries should be replaced as soon as possible. Note that this issue isn't specific to STF, it's just what happens over time. You should be prepared to replace the batteries every now and then. In any case, we consider 2 years per battery pack to be fairly good value for a device lab.

You should set up your devices so that the display is allowed to turn off entirely after a short timeout. 30 seconds or so should do just fine, STF will wake it up when necessary. Otherwise you risk reducing the lifetime of your device.

Note that you may have a problem if your USB hubs are unable to both provide enough power for charging and support a data connection at the same time (data connections require power, too). This can cause a device to stop charging when being used, resulting in many charging cycles. If this happens you will just need to get a better USB hub.

Is the system secure?

It's possible to run the whole user-facing side behind HTTPS, but that's pretty much it. All internal communication between processes is insecure and unencrypted, which is a problem if you can eavesdrop on the network. See our quick note about security.

Can I just put the system online, put a few devices there and start selling it?

Yes and no. See "Is the system secure?". The system has been built in an environment where we are able to trust our users and be confident that they're not going to want to mess with others. In the current incarnation of the system a malicious user with knowledge of the inner workings will, for instance, be able to control any device at any time, whether it is being used by someone or not. Pull requests are welcome.

Once I've got the system running, can I pretty much leave it like that or is manual intervention required?

In our experience the system runs just fine most of the time, and any issues are mostly USB-related. You'll usually have to do something about once a week.

The most common issue is that a device will lose all of its active USB connections momentarily. You'll get errors in the logs but the worker process will either recover or get respawned, requiring no action on your side.

Below are the most common errors that do require manual intervention.

One device worker keeps getting respawned all the time

Rebooting the device usually helps. If the device stays online for long enough you might be able to do it from the UI. Otherwise you'll have to SSH into the server and run adb reboot manually.

This could be a sign that you're having USB problems, and the device wishes to be moved elsewhere. The less complex your setup is the fewer problems you're going to experience. See troubleshooting.

We're working on adding periodic automatic restarts and better graceful recovery to alleviate the issue.

A whole group of devices keeps dying at once

They're most likely connected to the same USB hub. Either the hub is bad or you have other compatibility issues. In our experience this usually happens with USB 3.0 hubs, or you may have a problem with your USB extension card. See recommended hardware.

A device that should be online is not showing up in the list or is showing up as disconnected

If you've only got 9-12 devices connected and an Intel (Haswell) processor, it's most likely an issue with the processor. If your BIOS has an option to disable USB 3.0, that might help. If not, you're screwed and must get a PCIE extension card with onboard controllers.

The device might not have a unique USB serial number, causing STF to overwrite the other device instead

This has never happened to us so far, but we do have one dirt-cheap Android 4.4 device whose serial number is the wonderfully unique "0123456789ABCDEF". Presumably if we had more than one unit we would have a problem.

A device that was previously connected no longer shows up in the list.

Again, there can be various reasons for this behavior as well. Some common reasons are:

The device ran out of power

You can see the last reported power level in the device list, unless there was a lengthy power outage preventing the battery level from being reported.

Someone accidentally disabled USB debugging remotely

Yes, it happens.

An OS update disabled USB debugging

Yes, it happens. Especially on Fire OS.

Someone touched the USB cable just the wrong way causing a disconnection

Happens easily.

Your PCIE USB extension card died

Yes, it happens.

Temporary network issues

Can't help with that.

Someone removed the device physically.

Or that.

You're on Mac OS

There's a bug in ADB's Mac OS implementation that causes devices to be lost on error conditions. The problem is more pronounced when using USB hubs. You have to unplug and then plug it back in again.

The USB hub broke

Happens. Just try a new one.

Remote debugging (i.e. adb connect) disconnects while I'm working.

If you're using STF locally, the most common cause is that you're not filtering the devices STF is allowed to connect to. The problem is that once you do adb connect, STF sees a new device and tries to set it up. Unfortunately since it's already connected via USB, setting up the new device causes the worker process handling the original USB device to fail. This is not a problem in production, since the devices should be connected to an entirely different machine anyway. For development it's a bit inconvenient. What you can do is give stf local a list of serials you wish to use. For example, if your device's serial is 0123456789ABCDEF, use stf local 0123456789ABCDEF. Now you can use adb connect and STF will ignore the new device.

There's another likely cause if you're running STF locally. Even if you whitelist devices by serial in STF, your IDE (e.g. Android Studio) doesn't know anything about that. From the IDE's point of view, you have two devices connected. When you try to run or debug your application, Android Studio suddenly notices that two devices are now providing JDWP connections and tries to connect to them both. This doesn't really work since the debugger will only allow one simultaneous connection, which causes problems with ADB. It then decides to disconnect the device (or sometimes itself) entirely.

One more sad possibility is that your Android Studio likes to restart ADB behind the scenes. Even if you restart ADB, USB devices will soon reappear as they're still connected. The same is not true for remote devices, as ADB never stores the list anywhere. This can sometimes also happen with the Android Device Monitor (monitor).

Recommended hardware

This is a list of components we are currently using and are proven to work.

PC components

These components are for the PC where the USB devices are connected. Our operating system of choice is CoreOS, but any other Linux or BSD distribution should do fine. Be sure to use reasonably recent kernels, though, as they often include improvements for the USB subsystem.

Our currently favorite build is as follows. It will be able to provide 28 devices using powered USB hubs, and about 10 more if you're willing to use the motherboard's USB ports, which is usually not recommended for stability reasons. Note that our component selection is somewhat limited by their availability in Japan.

You can connect up to two of the older hubs (providing up to 8 devices total) directly to the motherboard without exhausting USB host controller resources.

We also have several "budget builds" with an MSI AM1I motherboard and an AMD Athlon 5350 4-core processor. These builds, while significantly cheaper, sometimes completely lose the USB PCIE extension cards, and even a reboot will not always fix it. This may normally be fixable via BIOS USB settings, but unfortunately the budget motherboard has a complete lack of any useful options. Fortunately the AMD processor does not share Intel's Haswell USB host control resource problem, so you can also just connect your hubs to the motherboard directly if you don't mind sharing the root bus.

Below is an incomplete list of some of the components we have tried so far, including unsuitable ones.

Tested equipment

Note that our hardware score ratings only reflect their use for the purposes of this project, and are not an overall statement about the quality of the product.

Our current recommendation is StarTech.com's PEXUSB3S44V. It provides an independent Renesas (allegedly Linux-friendliest) µPD720202 host controller for each port. Another option from the same maker is PEXUSB400, which also works great but may offer slightly less future proofing.

Our 玄人志向 USB3.0RX4-P4-PCIE cards have been nothing but trouble and we've mostly phased them out by now. Chipset-wise it's pretty much the same thing as StarTech's offering, but the SATA power connector is awfully flimsy and can actually physically break off. The card is also incredibly sensitive to static electricity and will permanently brick itself, which happened on numerous occasions.

The best hub we've found so far is Plugable's USB 2.0 7 Port Hub with 60W Power Adapter. It's able to provide 1.5A per port for Battery Charging spec compliant devices, which is enough to both charge and sync even tablets (although charging will not occur at maximum speed, but that's irrelevant to us). Note that even devices that are not compliant will usually charge and sync just fine, albeit slower. The more recent USB 3.0 version has proven unreliable with the rest of our components, causing the whole hub to disconnect at times. Annoyingly the ports face the opposite direction, too. Note that ORICO also provides hubs that are identical to Plugable's offerings, the latter of which seem to be rebrands.

Unfortunately Plugable's USB 2.0 hub is not perfect either, at least for our purposes. It includes a physical on/off switch which can be especially annoying if your devices are in a regular office with occasional scheduled power outages. This will shut down the PC too, of course, but the problem is that once power comes back online, the hubs will be unable to switch themselves on and the devices won't charge, leading you to find a bunch of dead devices the next Monday.

The System TALKS USB 2.0 hub is very reliable, but has a few annoying drawbacks. First, the power adapter only provides power to two of its four ports, while the other two are powered by the host PC. The problem with this approach is that you must figure out which devices are power hungry yourself and put them on the ports with higher current. This can complicate device setup/positioning quite a bit. Another drawback is that if the host PC is turned off, only the powered ports will keep charging the connected devices. However, the hub is amazingly compatible with pretty much anything, making it the top choice for older devices that do not support the Battery Charging hubs.

Most powered USB 3.0 hubs we've tested have had a serious problem: the whole hub occasionally disconnected. This may have been caused by the specific combination of our components and/or OS, but as of yet we don't really know. Disabling USB 3.0 may help if you run into the same problem.